Is it worth the cost to make a 2/1 into a 2/2?

[Tom Conant]

My wife and I just moved into a house on a 1/2 acre lot in Fresno with large detached 3 car garage with a kitchen and bathroom on the back of the property.  My goal is to convert it to an 1100 sqft second house (which it looks like anyway until you realize 70% of the square footage is garage space).

It will have it's own private driveway, car port, and a fenced yard to separate it from our part of the property.

Our goal is to create a mid term rental for traveling nurses.  At minimum, the kitchen and bathroom will be updated, and the garage will be converted into 2 bedrooms and a living room.

I've considered adding an addition bathroom into this space as well.  My question is if this will be worth the money as I will need to dig into the concrete slab foundation and tie into the existing sewage line.  It's possible that I may even need to increase the size of the entire sewage line depending on the size it is currently.

A second bathroom would make the space ideal for a pair of traveling nurses, but it is also a significant cost added to the project.

For those specializing in this space, I would love to hear feedback on how valuable the second bathroom will be.